1. Field of the Invention
The present invention relates to an IC (Integrated Circuit) contactor which is generally called an IC socket and, more specifically, to an IC contactor for use in a socket unit of a burn-in board or an IC test handler.
2. Description of the Related Art
FIG. 1 shows a prior art IC socket (IC contactor). In FIG. 1, reference numeral 1 denotes a body of the IC socket; 4, an IC positioning table; 5, an IC to be tested, fitted into a positioning recess of the table 4; 2, a plurality of contact pins arranged on opposing sides of the table 4 and in a direction perpendicular to FIG. 1; 3, separators each for separating adjacent contact pins 2; and 6, external lead pins (IC leads) extending from opposing sides of the IC 5. The IC 5 is pressed downward (in the direction indicated by the arrow in FIG. 1) by means of a cover member (not shown), so that the lead pins 6 are in contact with their respective contact pins 2, and the contact pins 2 are connected to an IC testing device (not shown).
FIG. 2 is a side view of one of the contact pins 2, FIG. 3 is a perspective view of the contact pins 2 arranged on one side of the IC 5, and FIG. 4 is a cross-sectional view taken along the line IV--IV of FIG. 1.
In the prior art IC socket, as shown in FIG. 1, the IC 5 is positioned by fitting the underside of the IC 5 into the recess of the IC positioning table 4, and the IC 5 is pressed in the direction of the arrow to bring the IC leads 6 into contact with the contact pins 2. By doing so, good contact for measurement of the IC 5 is attained. The contact pins 2 are arranged at regular pitches in the same direction, as illustrated in FIG. 3, and the separators 3 are each inserted between adjacent contact pins 2, as shown in FIG. 4, in order to prevent them from being short-circuited.
In the prior art IC socket described above, a pitch between the IC leads 6 is narrowed in accordance with a great increase in degree of integration of the IC; accordingly, pitches P between the contact pins 2 and between the separators 3 decrease, as shown in FIG. 4. The IC leads 6 tend to curve toward arrows A of FIG. 4 within the allowable range and, in this case, the IC leads 6 shift from the contact pins 2 or drop therefrom, thereby causing a drawback wherein not only normal contact cannot be obtained between the IC leads and contact pints, but also the IC leads may be deformed further.
More specifically, since the width (indicated by R in FIG. 4) of each of the contact pins 2 is gradually reduced in accordance with high degree of integration of the IC, the IC leads 6 drop from the contact pins 2 or, even if not, they are deformed so that only the small portions thereof are located on the contact pins 2. Thus, bad contact occurs in a test for the IC to be tested. If the width of each of the contact pins 2 is increased, the thickness (indicated by S in FIG. 4) of each separator 3 between adjacent contact pins has to be decreased because the pitches of the contact pins are restricted. For this reason, the molding and shaping of the separators 3 are very difficult to execute, and the separators are decreased in mechanical strength and durability.